the Brabus V6 Raid Daytona steering wheel then obviously you'll need to remove the old wheel to fit the new one.
If your steering wheel has a faulty angle sensor then you'll need to get the wheel off to swap it over. If the
airbag has gone off you will need to get it off to access the fixings to remove the detonated airbag.
Disconnect the battery for 10 minutes before removing the steering wheel.
Straighten the wheel and undo the single bolt underneath with a Torx 40 bit.

This is what the bolt looks like under the casing.

With the torx bolt loosened, carefully pull the wheel towards you.

Unplug these connections before pulling the wheel all the way off (circled).

The steering wheel has either 1 or 2 connectors, one airbag (red)
and the other for ESP (black). ESP is only present in Gen2 smarts.

If you are fitting a new steering wheel to a 700cc smart it will need to be aligned
electronically by smart. Failure to have the angle sensor aligned will cause the ABS and ESP
lights to illuminate fully on the dashboard. All safety systems are then deactivated (not good).
You don't necessarily have to go to a dealer, any specialist with Win-Star or MB-Star can do it.
Fitting a 600cc steering wheel is simple as there is no alignment required.
Fitting a 451 steering wheel doesn't seem to require alignment either.
Disassembling A Standard Wheel
Have a look at the dedicated steering wheel disassembly page here.